Senior Protein Chemistry Scientist – Drug Discovery

Position Summary
We are seeking a highly motivated and experienced Protein Chemist to join our Structural Biology and Protein Production team within the Protein Science & Technology Department. The successful candidate will play a critical role in accelerating gene-to-structure workflows and antibody discovery programs, integrating expertise in protein engineering, recombinant protein production, biophysical characterization, biologics purification and structural biology.
This is a highly collaborative role supporting small-molecule and biologics drug discovery programs. The ideal candidate will bring strong hands-on expertise in protein expression, purification, antibody purification, analytical characterization, and protein quality assessment, with a proven ability to deliver high-quality proteins, antibodies, and protein complexes for downstream applications.
The candidate will contribute to multiple programs focused on developing Client therapeutics and enabling technologies designed to accelerate translation of drug discovery programs toward clinical development. The successful candidate will work closely with protein chemists, structural biologists, assay scientists, and other cross-functional partners in a fast-paced, matrixed environment.
Summary of Essential Functions

• Independently design and optimize recombinant protein constructs for expression and downstream applications.
• Perform transfection of plasmids into mammalian cells, cell line maintenance, generation of baculovirus, and protein expression in insect (Sf9) and mammalian systems.
• Express recombinant proteins using bacterial expression systems and optimize conditions to maximize yield, solubility, and quality.
• Develop, optimize, and execute protein purification workflows using chromatography techniques including affinity, ion-exchange, hydrophobic interaction, and size-exclusion chromatography (SEC).
• Develop and execute purification strategies for antibodies, antibody fragments, and antibody-containing complexes.
• Perform antibody purification and QC, including assessment of purity, aggregation, integrity, concentration, and overall sample quality using appropriate analytical methods.
• Characterize purified proteins and antibodies using a broad range of biochemical and biophysical techniques, including analytical SEC/HPLC, SDS-PAGE, intact-mass analysis where applicable, DSF/thermal shift assays, BLI, SPR, and other analytical assays.
• Establish and apply protein and antibody quality-control criteria to ensure samples are suitable for structural studies, binding assays, biochemical assays, immunization campaigns, and other downstream applications.
• Evaluate protein and antibody stability, homogeneity, aggregation state, concentration, and batch-to-batch consistency; identify potential quality issues and implement appropriate corrective strategies.
• Troubleshoot recombinant protein and antibody expression, purification, and stability challenges to improve yield, purity, monodispersity, and functional quality.
• Generate high-quality protein samples and protein complexes for X-ray crystallography, cryo-EM, biophysical studies, biochemical assays, and other structural biology applications.
• Support antibody discovery programs by providing purified and well-characterized antibody molecules and complexes for downstream functional and structural characterization.
• Independently plan and execute small- and large-scale expression, purification, and characterization experiments while effectively managing multiple projects and priorities.
• Contribute to the daily operations of a highly productive protein production laboratory, including maintaining equipment, improving workflows, and supporting laboratory development and technology implementation.
• Analy…